GEOLOGY 28T 



GREAT ERUPTION OF MOUNT ETNA. 



MOUNT ETNA, which for some years has remained dormant, experi- 

 enced a very violent and long continued eruption during the past 

 year. The eruption commenced on the 20th of August, the same day 

 on which the terrific earthquake of St. Jago de Cuba occurred, and 

 continued with greater or less activity until the 17th of November 

 following. 



The indications of its approaching activity were, as usual, the drying 

 up of wells in the neighborhood, the duration of most dense clouds of 

 white smoke which rose like a vast pine tree, hollow rumbling sounds, 

 and three violent shocks, as of an earthquake. Shortly after, towards 

 the east, two new mouths were opened in the site which is known 

 under the name of the Valle del Leone. At first only clouds of a very 

 fine ash were thrown up ; which completely covered all the land near 

 the mountain, and quantities of which being taken up still higher by 

 an impetuous wind, were carried far off into the sea. These, however, 

 were but a small instalment of what was to follow. Immediately after- 

 wards an immense body of lava was vomited forth ; which precipitating 

 itself down the mountain with the violence of a torrent, divided into 

 three streams. One of these flowed in the direction of Zaffarana 

 another in the direction of the Comune of Giarra, more particularly 

 on an estate called Milo, near Giarra. To give an idea of the 

 immense quantity of liquid fire that was thrown out, official state- 

 ments describe this river of lava as being two miles in breadth at the 

 greatest, and ten palms in depth, whilst the rapidity with which it 

 moved was such as to cover in one hour a space of not less than 160 

 palms in extent. It seems, that in a very short time, in consequence 

 of the increasing strength of the eruption, the new mouths were 

 broken up so as to form one only ; from which masses of rock and 

 cinder were thrown into the air to a great height, and falling on the 

 wide extent of country round, carried with them the most fearful 

 ruin. The utmost intensity of the eruption perhaps took place on the 

 25th, 29th, and 30th of August, and on the 4th of September. The 

 rumbling subterraneous thunders were then incessant, as was also 

 the shaking of the ground. To this add the clouds of smoke and 

 flame which rested like an imperial diadem on the summit and we 

 may form some faint idea of the magnificent and awful spectacle which 

 Etna on those days presented. 



The accidents of the land, and the greater or less quantity of materi- 

 als thrown out of the mountain, produced a great variety in the 

 course of the streams of lava. Sometimes they appeared to drag their 

 slow length along, sometimes to precipitate themselves with threaten- 

 ing violence, expanding widely till they covered vast spaces of land, 

 or twisting and twining into the most capricious sinuosities, and accord- 

 ing to the varying rapidity of their movements varying their depth 

 and extent. On the 22d of August the running lava is stated to have 

 been 18 palms deep, whilst on the 30th it had increased to 240 palms 

 in some places. On the 31st of August the eruption still continued 

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